Since OLED technology is developing rapidly, a large amount of research is developed around OLED technology. As one of the key technologies of OLED technology, OLED packaging technology has become one of the hot research topics.
Due to the special optical properties of the material of OLED devices, it is required to package OLED devices in a glove box with a low oxygen environment. If the water in a high concentration or oxygen enters into the glove box, the OLED devices will be damaged, thereby affecting a lifetime thereof.
The glove box is a laboratory equipment with a high-purity inert gas filled therein, and the active substance can be filtered from the glove box, namely an inert gas tank or a dry box for removing O2, H2O, and organic gas. The glove box is widely used to provide a dry, oxygen-free and dust-free environment for lithium-ion batteries, semiconductors, super-capacitors, special lights, laser welding, or brazing.
Therefore, the OLED packaging process is required to be performed in an environment with a low concentration of moisture or oxygen (such as less than 10 ppm). In general, a nitrogen gas is provided into the glove box in the OLED packaging process. Since the glove box is not a confined space, when a pressure in the glove box is reduced, moisture or oxygen molecules in the air will penetrate into the glove box, and a purification device or purification system is required to purify the protective gas in the glove box, so as to maintain a low-moisture and low-oxygen environment.
FIG. 1 is a schematic diagram showing a conventional purification device.
The conventional purification device comprises an inlet filter 21, a valve 22, a purification unit (or reactor) 23, a circulating blower 24, a cooler 25, and an outlet filter 26. Under the influence of the circulating blower 24 disposed outside, the purification unit 2 continuously purifies the protective gas in the glove box 1, so as to maintain the moisture and oxygen in the glove box 1 below 10 ppm.
When a concentration value of the moisture or oxygen in the glove box 1 detected by a sensing assembly (including an oxygen sensor 41 and a moisture sensor 42) is greater than 10 ppm, a purging process is performed for the glove box in an operating platform. Namely, the protective gas is provided for the glove box by a gas supply device 3, thereby reducing a concentration of moisture or oxygen in the glove box 1.
However, in the conventional operating platform, if the protective gas provided from the gas supply device 3 has a high concentration of moisture or oxygen, it cannot be detected by the conventional operating platform. Furthermore, the purification device 2 comprises only one sensing assembly. When a gas leak occurs in the glove box 1 or the purification device 2, or when a sensitivity of the sensor is reduced, resulting in an inaccurate detected value, the high concentration of moisture or oxygen in the glove box 1 cannot be detected.
As a result, it is necessary to improve the conventional operating platform, so as to solve the problems existing in the conventional technologies as described above.